Multi-pellet cartridge



MULTI -PELLET CARTRIDGE Sheet Filed Oct. 24, 1966 INVENTORS WILLIAM L. KINGHELOE ROBERT B. BENTON om wq 7,, m g w 3 m w. 5 0w m mnrwnl w l Nw \aofl N aw @mw. 4 r 6N N QM mm h MW. m m EA. 1 1 925. u ow ATTORNEY F 1969 w. L.. KINCHELOE ET AL 3,4

MULTIPELLET CARTRIDGE Filed Oct. 24, 1966 Sheet 2 of :5

66 as 82 62b 64 74 84 INVENTORS WILLIAM L. KINGHELOE ROBERT B. BENTON awk/W AT TORNE Y Feb. 25, 1969 w. 1.. KINCHELQE ET AL 3,429,262

MULTI-PELLET CARTRIDGE Filed Oct. 24, 1966 Sheet 3 of s INVENTORS WILLIAM L. KINOHELOE ROBERT B. BENTON AT TORNE Y United States Patent 3,429,262 MULTl-PELLET CARTRIDGE William L. Kincheloe, San Jose, and Robert B. Benton,

Santa \Clara, Calif., assignors to FMC Corporation, San

Jose, Calif., a corporation of Delaware Filed Oct. 24, 1966, Ser. No. 588,974

U.S. Cl. 102--38 15 Claims Int. Cl. F42b 02, 9/04 ABSTRACT OF THE DISCLOSURE A multi-pellet cartridge for single-shot and repeating firearms, with a barrel-like body containing a plurality of discrete bores for loading with standard sub-caliber cartridges and a self-contained mechanism for firing all the sub-caliber cartridges simultaneously.

In order-to protect the grenadier, the grenades contain delay fuses which become armed only after they have traveled at least 35 feet from the launcher. This dead zone so reduces the eifectiveness of this weapon, especially in jungle combat or an ambush such as is frequently encountered in South Vietnam, that the grenadier must rely on other weapons for his defense. Furthermore, having to contend with this dead zone greatly limits the support the grenadier can supply to a close-in assault.

Previous attempts to eliminate these problems have proved unsatisfactory for one reason or another. Providing the grenadier with an additional short-range weapon burdens him with too much to carry and use efi'iciently, though it is better than requiring him to look to other troops for protection at close range. Replacing the grenades with other ammunition more effective in close combat would do the job nicely, but until the present invention was made no such ammunition had been developed that did not either require undesirable modification of the launcher or involve too much expense to manufacture.

Accordingly, one of the objects of the present invention is to provide ammunition that can be used interchangeably in place of grenades in an unmodified M-79 grenade launcher to give it effective lethality from the muzzle out.

Another object of the present invention is to provide a new close-range cartridge for the M-79 grenade launcher which is sufllciently inexpensive to justify discarding it after a single use.

Another object of the present invention is to provide a new, highly lethal, close-range M-79 grenade launcher cartridge capable of extensive reloading.

Another object of the instant invention is to provide a new form of multi-pellet cartridge for other 40 mm. weapons, including single-fire and automatic types, such as the XM75 and modifications thereof.

Another object of the instant invention is to provide a new type of multi-pellet cartridge for other shoulder or hand-fired weapons of other calibers, that is interchangeable with the weapons standard cartridge.

Still another object of the instant invention is to proice vide a multi-pellet cartridge for greatly increasing the close range effectiveness of a relatively long range firearm.

Yet another object of the present invention is to provide a multi-pellet cartridge that is easily and quickly reloadable entirely by hand.

A further object of the present invention is to provide a multi-pellet cartridge for loading with sub-cartridges comprised of standard, smaller-caliber, commerciallyavailable ammunition.

A still further object of the present invention is to provide a firearm cartridge containing a plurality of discrete sub-caliber cartridges arranged such that all of the projectiles can be discharged simultaneously.

Further objects and advantages of the present invention will become apparent from the following description thereof, including the drawings in which:

FIGURE 1 is an exploded view in perspective of a multi-pellet cartridge according to this invention, showing each of the several elements;

FIGURE 2 is a view in section on a longitudinal plane, of the cartridge of FIGURE 1 in its assembled and loaded condition;

FIGURE 3 is a view in transverse section, taken along line 3-3 of FIGURE 2, showing the relationship of the firing pins to the sub-cartridges.

FIGURE 4 is a view in section on a longitudinal plane, of another version of the multi-pellet cartridge of this invention, showing it loaded and all its elements in their assembled position;

FIGURE 5 is a view in transverse section taken along the line 55 of FIGURE 4, showing the relative positions of the sub-cartridges and their firing pins;

FIGURE 6 is a view in section on a longitudinal plane, of a throw-away version of the multi-pellet cartridge of this invention;

FIGURE 7 is a view in transverse section taken along the line 77 of FIGURE 6, showing the relation of the firing plate to the sub-cartridges, and

FIGURE 8 is a front end view of the cartridge of FIGURES 6 and 7, showing how the cartridge base conforms to the configuration of the barrel assembly.

Broadly considered, and with reference to the version illustrated in FIGURES l-3, the multi-pellet cartridge of this invention comprises a base 10, a striker plate 12, an assembly of firing pins 14, a striker plate spring 16, a sub-cartridge retainer plate 18, and a multi-bore barrel 20. As shown in FIGURE 2, when this cartridge is assembled and loaded the striker plate 12, the firing pins 14, the spring 16, and the retainer plate 18 are enclosed by the base 10 and the barrel 20 and are so arranged that when the percussion primer 22 is ignited the striker plate 12 and the firing pins 14 are driven forward against the tension of the spring 16 until the pins 14 strike the sub-cartridges 24, firing them all simultaneously.

The barrel 20 of the multi-pellet cartridge shown in FIGURES l-3 contains eighteen bores 26, twelve evenly spaced in an outer circle and six-spaced uniformly in an inner concentric circle. Twelve firing pins 14, preferably formed as integral extensions of the striker plate base 28, coincide with an equal number of passages 30 through the retainer plate 18. In a loaded and assembled cartridge, the striker plate 12 is positioned such that every other passages 30a (FIG. 3) partially overlaps a pair of radially spaced sub-cartridges 24a (indicated by phantom lines) and alternate passages 30b partially overlap the corresponding sub-cartridges 2411. Consequently, when the cartridge is fired each of the six pins 14a strikes two sub-cartridges 24a, and each of the six pins 14b strikes a single sub-cartridge 24b.

The sub-cartridge retainer plate 18 is held against the sub-cartridges 24 by a screw 34 that is threaded into an anchor bore 36 in, and coaxial with, the barrel 20. The screw 34 is countersunk into the retainer plate 18 to provide a recess 38 which coacts with the recess 40 in the striker plate base 28 to hold the striker plate spring 16 between the screw 34 and striker plate 12. When the cartridge is assembled, the spring 16 is compressed and holds the striker plate base 28 against the cartridge base as shown in FIGURE 2, and the guide portion 28a of the base 28 extends into the guide port 10a of a base 10.

A plurality (four are illustrated) of equally spaced pins 42 in the base 10 cooperate with an equal number of generally L-shaped slots 44 in the barrel to provide a secure, yet quickly disengageable, fastening between the base and the barrel. As shown in FIGURE 2, when the barrel 20 and the base 10 are properly assembled, the barrels rearward portion 20a fits snugly around an annular relieved area 10b on the outside of the forward end of the base and the pins 42 are flush with the outside surface of the barrel.

Loading and assembling the cartridge of FIGURES 1-3 is a simple procedure that can be carried out by hand very quickly. The sub-cartridges 24 are inserted into the chambers in the barrel bores 26, the retainer plate 18 is positioned against the sub-cartridges 24 with a guide pin 46 (FIG. 2) projecting into the retainer plate guide port 48, and the retainer plate screw 34 installed and turned tight. The striker plate 12 and its spring 16 are then positioned with the firing pins 14 aligned with the retainer plate passages 30 and the spring extending between the recesses 38 and 40. The base 10, containing a primer 22, is then inserted into the barrel 20 with the striker plate guide 28a fitting into the base guide port 10a, and then rotated to lock the pins 42 into their slots 44. Disassembly is accomplished by just the reverse of this procedure.

Another version of the multi-pellet cartridge of this invention is illustrated in FIGURES 4 and 5. In this version the barrel 60 and the base 62 are threaded at 60a and 62a, respectively, to form a screw-type joint which also can be easily manipulated by hand. The striker plate 64 has a base 66 with axial extensions forming guides 68 and 70, the guide 68 projecting into the base guide port 62b and the oppositely extending guide 70 disposed in the barrel guide port 60b when the cartridge is assembled. A striker plate spring 72 extends between the end of the striker plate guide 70 and the bottom of the port 60b to pressure the striker plate base 66 against the cartridge base 62.

The cartridge of FIGURES 4 and 5, shown bored for eighteen sub-cartridges, contains twelve firing pins 74 slidably held in the sub-cartridge retainer plate 78 and positioned with respect to the sub-cartridges 80 in the same way as are their counterpart pins 14 in the version of FIGURES 1-3. The pins 74 are staked at both ends to prevent them from coming out of the retainer plate passages 76, and both ends of the passages 76 are chamfered to accommodate this staking so that the retainer plate will fit flush against the sub-cartridges regardless of which side faces them. When the percussion primer 82 is ignited, the striker plate 64 is driven forward and strikes the firing pins 74 which transmit this force to the sub-cartridges 80 to fire them.

In order to insert sub-cartridges in the outer ring of bores 84, the threads 86 in the barrel 60 are relieved at 86a, forming a rosette-shaped pattern as shown in FIG- URE 5, and the periphery of the retainer plate 78 is shaped correspondingly to provide a backing to cover substantially all of the heads of the sub-cartridges. This configuration also aids in properly positioning the retainer plate over the sub-cartridges, which positioning is finally assured by the pin 88 in the barrel 60 and its cooperating bore 90 in the plate 78.

For the purpose of preventing the striker plate 64 from accidentally striking the firing pins 74 as a result of a sudden jolt during handling or shipping, this cartridge is provided with a safety pin 92 that extends through the base 62 and the guide 68 of the plate 64. This pin also positively identifies the cartridge as different from the standard round, and is easily withdrawn by pulling on the ring 94 when the cartridge is to be used.

In loading and assembling the cartridge illustrated in FIGURES 4 and 5, sub-cartridges are inserted into their chambers in the barrel bores 84, the spring 72 placed in the bore 60b, and the retainer plate 78 positioned against the sub-cartridges. A primer 82 is fitted into the base 62, the safety pin 92 inserted through the base 62 and the guide 68, and the base 62 then threaded into the barre-l 60 and turned tight. As is evident from FIGURE 4, the forward portion 620 of the base 62 bears against the sub-cartridge retainer plate 78 to hold it against the sub-cartridge when the cartridge is fully assembled.

FIGURES 6, 7 and 8 illustrate yet another multi-pellet cartridge according to this invention which, in this case, is designed for discarding after a single use. In this version the barrel comprises a plurality of distinct subbarrels 102 that extend into the cartridge base 104 and are tightly held by the base skirt 104a which has been pressed or otherwise formed around them. As shown best in FIGURE 8, in a cartridge of this type designed for firing eighteen sub-cartridges, the individual sub-barrels 102 will fit snugly together when arranged with twelve in an outer ring and six in an inner ring. A center tube 106, which can be made from sub-barrel stock, provides a central support for the sub-barrels 102 and a place for anchoring the sub-cartridge retainer plate 108. The retainer plates anchor shaft is sized to fit tightly inside the center tube 106, and preferably splined at 112.

The striker plate 114 has an annular peripheral flange 116 (FIGS. 6 and 7) that serves as a firing pin for each of the sub-cartridges 118, and a guide 120 that extends into a guide port 122 in the sub-cartridge retainer plate 108. A generally star-shaped spring 124 bears against the sub-cartridge retainer plate 108 and holds the strike plate 114 against a seal 126 that prevents power loss from the percussion primer 128. In a manner analagous to that of the other versions of the cartridge, ignition of the primer 128 drives the striker plate 114 forward, causing the ring-like firing pin 116 to strike the sub-cartridges 118 and fire them simultaneously.

Loading and assembling this disposable-type cartridge is carried out as follows. The sub-barrels 102 and the center tube 106 are grouped together as shown in FIGURE 8, the sub-cartridges 118 inserted in their chambers, and the retainer plate 108, the spring 124, and the striker plate 114 installed in that order. The base 104 containing the seal 126 then is placed over these elements to enclose them as shown in FIGURE 6, the base skirt 104a deformed around the barrel 100, and a primer 128 pressed into place in the base 104.

Although only barrels with smooth bores have been illustrated in the drawings, part or all of the bores can be rifled if desired. Extensive test firing of 40 mm. multipellet cartridges, some with all bores rifled and others with both rifled and smooth bores, indicates no significant difference in projectile dispersion pattern on targets at 50 yards.

From a weight viewpoint, the multi-pellet cartridges of this invention compare very favorably with alternative ammunition or weapons which they can supplant. For example, a 40 mm. cartridge of the type shown in FIGURES 4 and 5 weighs but 11 ounces when fully loaded with eighteen .22 short rimfire cartridges and a No. 2 /2 Remington large pistol primer, with the three-inch barrel and the base fabricated of 7076-T6 aluminum, and the firing pins, striker plate, and sub-cartridge retainer plate fabricated of SAE 1018 steel. A 40 mm. cartridge of the type illustrated in FIGURES 6-8, when constructed of the same material and loaded with the same type cartridges and primer, is even lighter, weighing but 8 ounces.

The recoil from the 40 mm. multi-pellet cartridge, loaded with eighteen .22 short rimfire cartridges, is approximately the same as that from a standard .30 caliber cartridge with a ISO-grain bullet fired in an M1 rifle or a standard 7.62 mm. cartridge fired from an M14 rifle. Tests have shown the recoil of the 40 mm. multi-pellet cartridge to only slightly exceed that experienced when firing a standard M406 grenade in the M79 grenade launcher.

Since the length and diameter of the 40 mm. size multipellet cartridge preferably are the same as that of conventional rounds for the M-79 grenade launcher, this this cartridge is interchangeable with these rounds. Accordingly, no modification of this or other 40 mm. weapons using similar ammunition, such as the XM75 or developments thereto, is needed in order for them to accept this cartridge.

Although they are especially valuable for swiftly con verting a 40 mm. grenade launcher into a close combat weapon, it also should be understood that the multipellet cartridges of this invention can be fabricated in sizes both smaller and larger than 40 mm. for use in other weapons, including single-fire, semi-automatic and automatic, and for other purposes than warfare.

Multi-pellet cartridges designed for eighteen sub-cartridges have been illustrated here only for purposes of explanation, and it should be understood that the invention includes similar cartridges designed and adapted for firing more or less than eighteen sub-cartridges. Furthermore, munitions other than .22 short rimfire cartridges can be used as sub-cartridges; for example, .22 longs and .22 long rifles can be interchanged with .22 shorts, and cartridges of smaller and larger calibers, Gyrojets (tradename of M. B. Associates, San Ramon, Calif.), and other types of projectiles that contain their own propellant and that can be fired by a firing pin, all can be used with appropriate modification of the number and size of the cartridge barrel bores and the position of the firing pins.

Though a No. 2 /2 Remington large pistol primer has been found very satisfactory for 40 mm. size multi-pellet cartridges loaded with eighteen .22 short sub-cartridges, other primers such as a No. 120 large rifle primer also can be used within the scope of this invention.

Although the best mode contemplated for carrying out the present invention has been herein shown and described, it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention as set forth in the appended claims.

Having completed a detailed description of the invention so that those skilled in the art could practice the same, we claim:

1. An expendable multi-pellet cartridge suitable for cyclic use in repeating firearms for firing simultaneously a plurality of projectiles through a plurality of bores, comprising:

(1) a cartridge base adapted to receive a percussion primer,

(2) a cartridge barrel secured to said base and having a plurality of bores for holding sub-cartridges and conducting projectiles fired from said sub-cartridges,

(3) sub-cartridge retainer means spaced rearwardly of said sub-cartridges and engageable with portions of the opposed outer ends thereof for holding the same in said bores of said barrel,

(4) sub-cartridge firing means adapted to intercept the plane of said retainer means and directly engage said sub-cartridges for percussion firing the same in said bores of said barrel,

(5) striker means for forcing said sub-cartrigde firing means to strike and fire sub-cartridges, and

(6) flexible means for retaining said sub-cartridge firing means spaced from said cartridge barrel and any sub-cartridges which said barrel may contain,

said cartridge base, cartridge barrel, sub-cartridge retainer means, sub-cartridge firing means, strike means, and flexible means inter-associated so that when said multipellet cartridge is loaded with at least one sub-cartridge and a percussion primer, the ignition of said primer causes said striker means to overpower said fiexible means and force said sub-cartridge firing means against said subcartridge to fire it, said multi-pellet cartridge when assembled having external dimensions commensurate with a standard cartridge for the particular firearm in which it is to be used.

2. The multi-pellet cartridge of claim 1 wherein said cartridge barrel is removably secured to said cartridge base to facilitate reloading of said cartridge.

3. The multi-pellet cartridge of claim 1 wherein said sub-cartridge firing means is integral with said striker means.

4. The multi-pellet cartridge of claim 1 wherein said sub-cartridge retainer means is removably secured to said cartridge barrel by rotatable locking means.

5. The multi-pellet cartridge of claim 1 wherein said cartridge barrel is comprised of a plurality of individual sub-barrels rigidly and non-removably secured to said cartridge base.

6. The multi-pellet cartridge of claim 5 wherein said sub-cartridge firing means is integral with said striker means.

7. The multi-pellet cartridge of claim 1 wherein said cartridge barrel contains bores for firing eighteen subcartridges.

8. The multi-pellet cartridge of claim 7 wherein said firing pin system comprises twelve firing pins annularly spaced such that every other pin strikes two sub-cartridges and the remaining pins each strike one sub-cartridge when the said cartridge is fully loaded and fired.

9. The multi-pellet cartridge of claim 8 wherein said cartridge barrel is removably secured to said cartridge base by interlocking slots and pins, said firing pins are integral with said striker plate, and said retainer plate is removably secured to said cartridge barrel.

10. The multi-pellet cartridge of claim 7 wherein said cartridge barrel comprises eighteen substantially tubular sub-barrels rigidly and non-removably enclosed in part by said cartridge base, and said firing pin system comprises an annular flange extending from said striker plate toward said cartridge barrel.

11. An expendable multi-pellet cartridge suitable for cyclic use in repeating firearms for firing simultaneously a plurality of projectiles through a plurality of bores, comprising:

(1) a cartridge base adapted to receive a percussion primer,

(2) a cartridge barrel secured to said base and having a plurality of bores for holding sub-cartridges and conducting projectiles fired from said sub-cartridges,

(3) sub-cartridges retainer means for holding subcartridges in said bores of said barrel,

(4) sub-cartridge firing means for percussion firing sub-cartridges in said bores of said barrel, said firing means being carried by said retainer means, and movable therewith,

(5) striker means for forcing said sub-cartridge firing means to strike and fire sub-cartridges, saidstriker means before ignition of said percussion primer being spaced from said firing means, and

(6) flexible means for retaining said sub-cartridge firing means spaced from said cartridge barrel and any sub-cartridges which said barrel may contain,

said cartridge base, cartridge barrel, sub-cartridge retainer means, sub-cartridge firing means, striker means, and flexible means inter-associated so that when said multi-pellet cartridge is loaded with at least one subcartridge and a percussion primer, the ignition of said primer causes said striker means to overpower said flexible means and force said sub-cartridge firing means against said sub-cartridge to fire it, said multi-pellet cartridge when assembled having external dimensions commensurate with a standard cartridge for the particular firearm in which it is to be used.

12. The multi-pellet cartridge of claim 11 wherein said sub-cartridge firing means is separate from said striker means and held by said sub-cartridge retainer means in movable relationship therewith.

13. The multi-pellet cartridge of claim 11 wherein said sub-cartridge retainer means is removably secured against sub-cartridges by said cartridge base.

14. The multi-pellet cartridge of claim 11 containing removable safety means for holding said striker means to said cartridge base in spaced relation to said sub cartridge firing means when said striker means is pressured toward said cartridge barrel.

15. The multi-pellet cartridge of claim 11 wherein said cartridge barrel contains bores for firing eighteen subcartridges and said firing pin system comprises twelve firing pins annularly spaced such that every other pin strikes two sub-cartridges and the remaining pins each strike one sub-cartridge when said cartridge is fully loaded and fired, said barrel being removably threaded to said cartridge base, and said firing pins being separate from said striker plate and held by said retainer plate in movable relationship therewith.

References Cited UNITED STATES PATENTS 490,614 1/1893 Redwine 10241 X 1,660,590 2/1928 Baldwin.

ROBERT F. STA'HL, Primary Examiner. 

